https://www.irjet.net/archives/V9/i3/IRJET-V9I3235.pdf

1. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 09 Issue: 03 | Mar 2022 www.irjet.net p-ISSN: 2395-0072
© 2022, IRJET | Impact Factor value: 7.529 | ISO 9001:2008 Certified Journal | Page 1281
Design and Analysis of a Cooling System for High Voltage Battery Pack
of a Formula Student Electric Vehicle
Hammad Khurshid1, Eram Naz2
1Student, Department of Mechanical Engineering, Faculty of Engineering & Technology, Jamia Millia Islamia, New
Delhi, India
2Student, Department of Electrical Engineering, Faculty of Engineering & Technology, Jamia Millia Islamia, New
Delhi, India
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Abstract - This paper explains how to construct a high-
voltage battery pack for a formula student vehicle and how to
choose a cooling system, as well as easy analysis tools for
developing an efficient cooling model. We can display heat
dissipation and cooling flow just like a genuine system using
software like Ansys Icepack. This system is designedaccording
to the formula student's handbook and with cost-effectiveness
in mind.
Key Words: Air cooling system, thermal model, battery
pack, heat generation, energy storage, battery thermal
management
1.INTRODUCTION
To operate an electric car at a high degree of efficiency, the
electric motor, power electronics, and battery pack must all
be kept within a certain temperaturerange.Thisinvolvesthe
implementation of an advanced heat management system.
Fig 1-Battery box exploded view
Fig 2- Battery Box
To handle our heat radiations in the accumulator, motor,
and motor controller, we use a 'FanBasedCoolingSystem.'It
is dependent on the ambient air, which carries the heat via
the batteries.
The A123-AMP20m1HD-A pouch cells feature a nominal
voltage of 3.3V, a capacity of 19.6Ah, a total weight of 496g
for 96 cells, and a power discharge of 1200W.
An efficient cooling system is required to control the heat
dissipation of such power.
2. THERMAL DESIGN FLOW
An extremely efficient designflow is required tosustaina
basic cooling system. We use active air conditioning to
manage heat generation in this system. When the vehicle is
driving at high speeds, special air flow channels are built to
direct air, and when the vehicle is stationary, fans are
employed to force air to the battery accumulator box.

2. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 09 Issue: 03 | Mar 2022 www.irjet.net p-ISSN: 2395-0072
© 2022, IRJET | Impact Factor value: 7.529 | ISO 9001:2008 Certified Journal | Page 1282
Fig 2- Thermal Design Flow Chart
For active airflow, the accumulator box features three intake
and three exhaust fans. By readings from a thermal probe
used to monitor battery temperature, special temperature
sensors are employed to adjust the fan speed.
3. HEAT GENERATION METHODS-
Chemical processes heat, polarization heat, and Joule's heat
are the three types of heat created by a lithium ion battery.
Because characterizing all of the fundamental physical and
electrochemical processes that occur in a battery cell is
challenging and time-consuming, the battery is evaluated
using parametric analysis and characterized using a
mathematical model method based on external observable
behaviors. All three variables can be measured in real time:
voltage at the battery terminal Vt, current A, and
temperature C.
● Thevenin Equivalent Method
➢ Vd=I×R
➢ Q = 𝐼 2𝑅
➢ Q= 0∫t 𝐼2 𝑅𝑇𝑑x
Table 1- Heat Dissipation Data
4. COOLING MODEL
The cooling method employed is forced convection usingsix
fans to transport heat out of the batteries and improve the
surface area of heat convection. There are six stacks, each of
which has 16 battery cells. These 16 battery cells are
connected in series, and each pack of four battery cells is
connected in parallel. The crevices between the stacks are
lined with aluminum sheets that act as heat sinks to
dissipate the heat.
Fig 3- Cell Configuration
The inlet fans are located on the lower half of the battery
box's inlet face, while the exhaust fans are located on the
upper half. The natural thermal movement of air is aided by
this type of positioning.
The air ducts beneath the automobile direct fresh air to the
intake fans, which drive airflow to the inlet fans of the
battery pack to travel through the cells and heat sinks to
dissipate heat and out the exhaust fans at high speeds.

3. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 09 Issue: 03 | Mar 2022 www.irjet.net p-ISSN: 2395-0072
© 2022, IRJET | Impact Factor value: 7.529 | ISO 9001:2008 Certified Journal | Page 1283
Fig 4-Fan placement & Heat flow
5. FAN SELECTION
Choosing the most efficient cooling fan for the system is a
critical task. The fan performance curve is simply a static
pressure curve created by charting various static pressure
points against precise volumetric flow rates at a certain test
speed, giving a foundationforflowandpressurecalculations.
The static pressure curve, which shows the fan's
performance at a given speed, can also be used to figure out
the pressure capability.
For our method, there were a few criteria for picking fans:
1. Axial fans are used because they canproducea higherflow
rate than other types of fans.
2. Because the low voltage system was 12 volts, the fans
necessary had to be 12 volts as well.
3. We looked at all of the 12V DC fans on the market and
investigated their designs to find the best one.
4. We looked at the fan performance curve and found that
124CFM is the best we could come up with.
5. To make the system basic and stable, we chose a Saneo
Denki San Ace 92GV38 E simple fan with dimensions of
92x92x38mm.
Fig 6- Fan Speed Curve
Fig 7-Fan dimensions
6. ANALYSIS
The batteries are cooled via forced convection, and six fans
are enough to maintain therequiredtemperatureatfull load,
with three parallel fans pushing air into the battery box and
three parallel fans pulling air out of the stack.
The system's intake and exit temperatures are depicted in
the diagram.
The greatest temperature measured in the hottest sectionof
the battery system was 520 C, which is well within the
operational temperature range.

4. International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056
Volume: 09 Issue: 03 | Mar 2022 www.irjet.net p-ISSN: 2395-0072
© 2022, IRJET | Impact Factor value: 7.529 | ISO 9001:2008 Certified Journal | Page 1284
Fig 8-Inlet View
Fig 9-Outlet View
Fig 10-Cross-section View
7. CONCLUSIONS
CFD study was performed to figure out how the 96-cell
cooling model, which produces 1200 W of power, works. A
better cooling system allows the system to run more
efficiently and increases its longevity. This straightforward
concept will boost cooling system efficiency while lowering
costs. Finally, with the proportions of the fan employed, this
type is the most efficient.
This battery pack was constructed accordingtothe rulesofa
formula student competition, and the best performing cells
were used in its construction.
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[4] A.A. Pesaran, Journal of Power Sources 110 (2002)
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[5] Ohzuk T, Brodd RJ. An overview of positive-electrode
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[6] The Boston Consulting Group. Batteriesforelectriccars:
challenges, opportunities and the outlook to 2020.
Retrieved January 2014.
[7] Omar N, Daowd M, Van den Bossche P, Hegazy O,
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